package org.aswing.event;

/*
 Copyright aswing.org, see the LICENCE.txt.
*/
import org.aswing.event.TreeModelEvent;

/**
 * Defines the interface for an object that listens
 * to changes in a TreeModel.
 * 
 * @author paling
 */
interface TreeModelListener {
/**
 * <p>Invoked after a node (or a set of siblings) has changed in some
 * way. The node(s) have not changed locations in the tree or
 * altered their children arrays, but other attributes have
 * changed and may affect presentation. Example: the name of a
 * file has changed, but it is in the same location in the file
 * system.</p>
 * <p>To indicate the root has changed, childIndices and children
 * will be null. </p>
 *
 * <p>Use <code>e.getPath()</code>
 * to get the parent of the changed node(s).
 * <code>e.getChildIndices()</code>
 * returns the index(es) of the changed node(s).</p>
 */
    function treeNodesChanged(e:TreeModelEvent):Void;

/**
 * <p>Invoked after nodes have been inserted into the tree.</p>
 *
 * <p>Use <code>e.getPath()</code>
 * to get the parent of the new node(s).
 * <code>e.getChildIndices()</code>
 * returns the index(es) of the new node(s)
 * in ascending order.</p>
 */
    function treeNodesInserted(e:TreeModelEvent):Void;

/**
 * <p>Invoked after nodes have been removed from the tree.  Note that
 * if a subtree is removed from the tree, this method may only be
 * invoked once for the root of the removed subtree, not once for
 * each individual set of siblings removed.</p>
 *
 * <p>Use <code>e.getPath()</code>
 * to get the former parent of the deleted node(s).
 * <code>e.getChildIndices()</code>
 * returns, in ascending order, the index(es)
 * the node(s) had before being deleted.</p>
 */
    function treeNodesRemoved(e:TreeModelEvent):Void;

/**
 * <p>Invoked after the tree has drastically changed structure from a
 * given node down.  If the path returned by e.getPath() is of length
 * one and the first element does not identify the current root node
 * the first element should become the new root of the tree.<p>
 *
 * <p>Use <code>e.getPath()</code>
 * to get the path to the node.
 * <code>e.getChildIndices()</code>
 * returns null.</p>
 */
    function treeStructureChanged(e:TreeModelEvent):Void;
}